1. Field of the Invention
The present invention generally relates to a communication system. More particularly, the present invention relates to a method and system for transmitting/receiving data to provide high-speed communication services to users in a communication system that provides a variety of communication services.
2. Description of the Related Art
Future-generation communication systems are under development in the form of mobile communication systems that provide services capable of high-speed large data transmission/reception to Mobile Stations (MSs).
As the future-generation communication systems are based on the mobility of MSs, the power consumption of the MSs is a significant factor to the whole system. In order to minimize the power consumption of the MSs, an idle mode operation and an active mode operation between the MSs and a Radio Access Station (RAS) functioning as a Base Station (BS) have been proposed. An idle mode was introduced for the purpose of minimized power consumption for an idle period of time in which no transmission occurs due to the absence of transmission data.
In general, when there is no more transmission/reception data during data transmission/reception between an MS and a RAS, the MS transitions from an active mode to an idle mode by de-registration. If a service is generated for the MS in the idle mode, the RAS transmits a paging message, for example, Mobile_Paging-Advertisement (MOB_PAG-ADV) to the MS and both the MS and the RAS enter into the active mode. The MOB_PAG-ADV message is broadcast to all MSs that the RAS can communicate with.
Upon receipt of the MOB_PAG-ADV message, the MS activates the applications of all service types that it supports before receiving data from the RAS because it cannot identify the service type of the data until it actually receives the data. This means that the applications are kept suspended until the MS receives the data. As a consequence, the MS suffers from unnecessary power and memory consumption.
As the MS maintains a radio connection with the RAS, that is, shares resources to be able to receive data of all service types, it also suffers from unnecessary resource consumption. In addition, the MS receives the communication service through an associated application after identifying the service type of the received data, thereby causing a time delay during data transmission/reception between the RAS and the MS.
Another problem with this data transmission/reception mechanism is that there is no specified data transmission/reception scheme for Instant Messaging (IM). Accordingly, there exists a need for a method for transmitting/receiving data in the case where an active-mode MS transmits/receives data to/from an idle-mode MS, that is, when an IM service is provided to users.